As electronic products developed towards the trend of compact design with the capability of transmitting massive amount of information and images, people's demands for compact flat-panel displays and better image quality is increasingly higher. Since the beginning of developments in organic light-emitting diode (OLED) devices, many people have been attracted to invest in research and mass production of OLED displays which are considered as one of the flat display technologies with the most development potential in succession to thin film transistor liquid crystal displays (TFT LCDs).
In addition to advantages such as self-luminescence, high response time characteristic (1us), power saving (with only one third power consumption of the TFT LCDs), wide viewing angle (180 degrees), wide color gamut (NTSC 100% or more), low operating voltage (3 to 10V), high contrast (as high as 104:1), more importantly, the OLED is favorable because of its slimness feature (a thickness of the panel may be less than 1 mm) together with self-luminescence and simplified panel structure for realizing a transparent mode display more easily. It could be applied in a new generation display panel.
While allowing transmission of lights from the outside environment to pass through a display structure, the transparent display panel is also capable of forming images by emitting image lights from pixels on the display. In order to achieve aforesaid effects, a plurality of holes are often formed on the existing transparent display panel, and then display pixels capable of emitting the image lights are disposed between those holes. Accordingly, users are able to observe images behind the display panel through the holes while viewing the images presented by the display pixels between the holes. However, aforementioned holes may also lead to diffraction effect when outside light pass through the holes. As such, transmissive images from behind the display panel may be too blur for the users to observe or presented in poor quality.